Sewing-machine-feed regulator



Nov. 9 1926.

A. GRIEB SEWING MACHINE FEED REGULATOR Filed Nov. 15, 1925 3 Sheets-Sheet 1 INVENTOR BY ATTORNEY.

wnusggs Nov. 9 1926.

A. GRIEB SEWING MACHINE FEED REGULATOR Filed Nov. 13, 1925 3 Sheets-Sheet 2 WITNEES ATTORNEY Nov. 9 1926.

A. GRIEB SEWING MACHINE FEED REGULATOR Filed Nov. 13, 1925 3 Sheets-Sheet 5 INVENTOR figs M 1 ATTORNEY WITNESSES. QM:

Patented Nov. 9, 1926.

T UNITED STATES PATENT ALFRED GBIEB, OF ELTZAIBETH, NEWJ'EBSEY, ASSIGNOB TO THE SINGEB-MANUFAC- TUBING COMPANY, OF ELIZABETH, NEW A CORPORATION OF NEW JER- SEY.

snwmc-mncnmn-rnn'n REGULATOR;

This invention relates to sewing machine feed-re atom and has for an object to provide'a eed-regulator of simplified construction which may be quickly and easily adjusted to. roduce any desired stitch-length 'and whic will retain its adjustment indefinitely.

' other object of the invention is to provide a' feed-regulator of compact construc-- tion, the parts of which will not become loose from wear and the manufacture of which-mayv be carried on without expensive machining operations. Further objects of the invention will appear from the following description and clalms.

4 To the attainment of the ends in view a full surface cylindrical contact is maintained between the feed-eccentric and a feed-adjusting eccentric, and a driving connection independent of the feed-adjusting eccentric is provided between the sewing machine shaft and the feed-eccentric. This driving connection comprises a working joint ermitting the feed-eccentric to artake of t e combined diametrical and side-shift movement imparted'to it by rotary adjustment of the feed-eccentric. In its preferred form the regulator comprises a cylindrical body-member having an axial bore to fit and be fixedlg secured to the sewing machine shaft. feed-adjusting disk having on one side a fiat face .and on its other side an eccentric hubextension is'mounted on the body-member with its flat face in contact with the adjacent fiat face of the bod member. The face of the feed-adjusting isk on the same side as the hub-extension is formed with a circular groove in the bottom of which is fitted an arcuate pressure late held in frictional engagement witht e flat bottom wall of the groove by means of spaced screws and spring-washers; such screws assing through an arcuate slot in the fee -adjusting disk and being threaded into the body-member. An anchor pin havin a cylindrical shank is assed througha ho e in the (pressure plate between the spaced screws an is fitted-to a hole in the b0 -memb'er. The anchor pin is formed with an enlar ed cylindrical head the sides of which are attened to fit into a radial slot in the inner flat face of a third disk-like member having an eccentric hub and an axial bore to, fit upon the eccentric hub of the intermediate or adjusting memher. The eccentric hub of the third member constitutesthe feed and-re turn eccentric of the-machine and is connected by the usual p tman and feed-rocker to the feed-dog. Another eccentric on the sewing machine shaft 1s connected as usual to im art rising and falling movements to the fee -dog. The peripheral portion-of the feed-adjusting disk is formed with a notch which may be engaged by a finger-lever mounted in the machine frame and locked against turning while the operator turns the sewing machine shaft by hand to effect a relative shift'of the body and ad usting member's, thus varying the eccentricity of the feed-eccentric relative to the ..ax1s of the sewing machine shaft.

The working contact between the eccentric hub of the adjusting member and the thirdor feeding member is a full. cylindrical surface contact, and the working contacts between the'head of the anchor in and the walls of the radial groove in t e third or feeding member are, flat surface contacts. I

The machined surfaces of the various parts are principally circular or cylindricahthus facilitating the manufacture of the dBVlCG 1n quantities on monitor lathes and reducing the number of remaining machining operations to a minimum. 'i

In the accompanying drawings, 1 is a front endelevation of a sewing machine embod ing the invention. Fig. 2- is a plan view of t e sewin machine bed plate showing the feeding mec anism therebelow. Fig. 3 is a sectional view transversely of the sewing machine main-shaft on the line3-3, Fi 2. Fig. 4' is a sectional view longitudina y of the sewing machine shaft on the line 44, Fig. 3. Fig. 5 is a face view of the device with the feed-eccentric -member removed.

Fig.6 is a section on the line 6-6, Fig. 5. Fig. 7 1s a disassembled pers ective view of? the p artsshown in 'Fig. 5. ig. 8 is a pers tive view of the feed eccentric-member" a one and Fig.9 is a dia rammatic view illlli tstratmgthe range of a justm'ent of the pa s..

In the embodiment ofthe trate'd 1 represents the bed ofa-sewing machine, 2' the standard, 3' the overhanging head, 4, the reciprocating. needle, 51 the resser-foot, 6 the cloth-plate-'and".,7f the invention illusi ooper which is mounted onthema in-sliafts,

I lev er 33 and turns the shaft 8 by hand until The feed-dog 9 is mounted on the feed-bar 10 which is fulcrumed at- 11 to the feed rocker 12, the latter being fulcrumed at 13 to the frame bracket 14. Rising-and-falling movements are'imparted to the feed-bar by means of the eccentric 15 fixed to the shaft 8 and embraced by one end of a link 16, the other end of which is connected at 17 to the feed-bar 10. Connected to the feed-rocker 12 is one end of the pitman 18 the other end of which embraces the adjustable feed-andreturnor feed-eccentric 19 to be described.

Fixed to the sewing machine shaft 8 is the body-member or supporting disk 20 having a flat face 21.. Mounted to turn on and relative to the shaft 8- is the intermediate disk 22 having the shaft aperture 23 and eccentric hub 24. The disk 22 has a flat face on one side which is held in frictional engagement with the flat face 21 of the body-member 20 by means of the spaced screws 25 and spring washers 26. The screws 25 pass through the spaced holes 27 in the friction plate 28 which islet into the circular groove 29 in the other face of the disk 22. These screws also pass through the semi-circular slot 30 in the disk 22. The edge of the disk 22 is notched at 31 to receive the locking nose 32 of the springpressed finger-lever 33 fulcrumed at 34 on the bed 1. v

Mounted on the eccentric hub extension 24 of the adjustingdisk 22 is the cylindrically apertured feed-eccentric 19 having at one end a disk-like head 35 the fiat face 36 of which is held close to or in engagement with the disk 22 by means of the collar 37.

A working joint between the feed-eccentric 19 and the shaft 8, preferably in the form of a single pin and slot anchorage, permits the eccentricity of the eccentric 19 to be regulated by rotatably adjusting the disk 22 relative to the shaft 8 and also causes the feed-eccentric to be driven by the shaft 8 to impart feed-and-return movements to the feed-rocker 12.

This working joint or one point'driving connection preferably comprises a radial slot 38 formed in the inner face 36 of the head 35 of the feed-eccentric. Into the slot 38 projects the enlarged head 39' of the anchor pin 39; the sides of the head 39' being fiattened at 4.0, 40, to snugly fit the slot as. The

pin 39 passes through a hole 41 in the friction-plate '28 and into the hole 42 in the body-member 20. It constitutes a driving connection, independent of the feed-adjusting disk 22, between the shaft 8 and the feedeccentric 19. i

A suitable scale 43 indicating stitches per inch may be formed on or secured to the body-member 20 and the cloth-plate 6 may be formed with a window 44 to expose such scale to the operator. To adjust the stitchlength the operator depresses the fingerthe nose 32 of the lever 33 enters the notch 31 in the adjusting disk 22. The operator then turns the shaft until the scale 43 indicates through the window 44-tl1e desired number of stitches per inch. This completes the adjustment.

It will be noted that most of the machined surfaces of the several parts of ale device are circular or cylindrical and that the working contacts between the parts are surface contacts rather than line or point contacts, thus insuring long continued effectiveness of the device and freedom from lost motion due to wear. The device is also of simple and compact construction and may be manufactured in quantities at low cost. As shown in Fig. 9, the working joint between the pin 39 and the walls of the slot 38 permits the feed-eccentric to follow or partake of the combined radial and side-shift movement imparted to it by rotary adjustment of the feed-adjusting eccentric. Since the cylindrical bore in the feed-eccentric closely fits the feed-adjusting eccentric, it follows that the shift of the feed-eccentric relative to the shaft 8 is not purely a diametrical shift but has a small side-shift component. The full line circles in Fig. .9 indicate the positions of the parts with the feed-adjusting eccentric 24 at one extreme position of adjustment. In this-position of adjustment the center d of the feed-eccentric 19 makes its closest approach to the center 6 of the shaft 8 and the resultant stitch length will be a minimum. By rotating the feed-adjusting eccentric 24 a out the'center 6 through the angle a, the center of the feed-adjusting eccentric will be shifted to c and the center of the feed eccentric will be shifted to (Z During this shift the-center 0 travels circularly about the center e to the position 0 and the angle d, 0', f remains constant and equals d 0 7. Also the distance d, 0' remains constant and equals d 0 'In the dotted line osition of the parts the stitch-length will e a maximum. While the path of movement of the center d is not purely diametrical of the shaft 8,its deviation from a diametrical path, such as w-m, is not great and no undesirable disturbance of the timing of .the feed-advancing movement results. The

greatest deviation occurs at the shortest stitch-length where there is a slight retardation of the feed-eccentric on the shafts.8. Such retardation is however without detrimental eifect.

The invention is not to be understood as limited to the form and arrangement of parts shown and described as it is obviously susceptible of material modification within the spirit and scope of the invention. Having thus set forth the nature of the invention. what I claim herein is 1. In a sewing machine feed-regulator, the combination with a sewing machine the shaft, of a feed-adjusting eccentric rotatable on and relatively to said shaft, a feed-eccentric having a cylindrical aperture fitted to said feed-adjusting eccentric, and a driv- 1 ng connection independent of said feed-adjusting eccentric between said shaft and feed-eccentric.

2. In a sewing machine feed-regulator,

the combination with a sewing machine" shaft, of a feed-adjusting eccentric rotatable on and relatively to said shaft, a feed-eccentric having a cylindrical aperture fitted -to said feed-adjustlng eccentric, and a driving connection' between said shaft and feed eccentric, said connection including a work ing joint permitting the feed-eccentric to partake of the combined diametrical and side-shift movement imparted to it by-roto and circularly adjustable about the axis' of said-shaft and formed with an eccentric surface, a feed-eccentric member having a cylindrical aperture fitted to the eccentric surface of said adjusting member, and a one oint anchorage between said shaft and eed-eccentric. I

4. In a sewing machine feed-regulator, combination with a body-member adapted to be fixed to a sewing machine shaft, of a feed-eccentric having a cylindrical aperture, an intermediate member frictionally secured to said body-member and having an eccentric hub fitted to the aperture in said feed-eccentric, and a single anchor pin-and-slot connection between said feed-eccentric and said body-member.

5. In a sewing machine feed regulator, a shaft, a-body member fixed to said shaft, a feed-adjusting member rotatable on and relatively to said shaft and having an eccentric portion, a feed-eccentricmember embracin the eccentric portion of said feedadjusting member and having a radially slotted face, and an anchor pin carried by said body member and entering the radial slot in the face of said feed-eccentric mem- 6. In a sewing machine feed-regulator, the combination with a. main-supporting member ada ed to be fixed to the sewing machine s'ha ft, of a feed-eccentric member havin a cylindrical bore and a radiall slotte disk-like head at one end of sai bore, an intermediate adjusting disk having an eccentric hub fitted to said a cylindrical bore, means jrictionallysecuring the intermediate disk to the main supporting member, and an anchor-pin, mounted 111' said main su porting member and entering the radial s ot in the head of the feed-eccentric member.

In testimony whereof, I have signed my name to this specification.

ALFRED GRIEB. 

